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1.
Abstract:  Research initiated in 1909 by G. Leslie Adkin (1888–1964) suggested Park Valley in the Tararua Range was glaciated during the Late Quaternary, based on the 'U-shaped' cross-profiles in the uppermost parts of several valleys. Findings were published, but were not met with universal acceptance. Adkin's work remained the only glacial research undertaken on the North Island's axial ranges until the latter part of the 20th century. Adkin holds a special position in New Zealand, because although he worked full-time as a farmer he published nearly 40 articles in scientific journals on topics as varied as Māori archaeology and geomorphology.  相似文献   

2.
Seasonal climate forecasts have been promoted as a means to increase the resilience of marginal groups in Africa. The manifestations of this are still to be seen. This paper argues that successful dissemination and adoption of the forecast requires an in-depth profile of the characteristics and needs of user groups. The case study of a mountainous village in southern Lesotho is used to highlight the decisions which one group of marginal users – smallholder farmers – might make in response to the forecast. A participatory role-play exercise explores what information households presently receive and how new climate forecast information could be integrated into seasonal decision making. Results show that there are a number of low-input options available to these farmers for responding to the forecast. Adoption, however, is going to require repeated exposure to the forecast in conjunction with forecast development that is suited to users' needs. The case study is linked back to the larger scale by suggesting paths that seasonal climate forecast development could take if it is to contribute to improving livelihood sustainability among marginal groups.  相似文献   

3.
In recent years, Māori and wider indigenous geographies have flourished. These include works by scholars identifying specific Māori or indigenous issues but less attention has been paid to the way such research is conducted. This paper engages with these developments and presents the practices and lessons learnt from one particular research collaboration. Relationship building, multiple methods, flexibility, communication choices and wider support are all noted as key elements in establishing a supportive and fruitful collaboration.  相似文献   

4.
The place of schools in parents' community belonging   总被引:1,自引:0,他引:1  
Abstract:  Schools are central community facilities in the daily lives of families with young children. The paper draws on survey and in-depth interview data to describe the role schools play in parents' sense of belonging to community. Māori and Pākehā parents indicated that schools and preschools were the most significant sites to their community belonging. They are a common meeting place, a source for community knowledge, and a point of departure for the development of parental friendship networks, and reciprocity in child care and support. Parents' perceptions of local schools in all socio-economic neighbourhoods influenced school choice and commitment to a neighbourhood. For Pacific and Asian parents schools were less significant as sites of community belonging.  相似文献   

5.
Abstract:  Pre-contact Māori regarded land and water as a single entity, with a common regime of resource management practices. Underpinning these was a world-view that involved unique spiritual concepts, the most important of which was mauri: the notion that a body of water had its own life-force. Waters were classified according to the state of their mauri. The paper outlines traditional approaches and how they are applied today.  相似文献   

6.
Since 1970, the worldwide distribution, frequency and intensity of epidemics of dengue and dengue haemorrhagic fever (DHF) have increased dramatically. In Indonesia, as elsewhere, the geographic distribution and behaviour of the two main vectors – Aedes aegypti and Aedes albopictus – and the consequent transmission dynamics of the disease are strongly influenced by climate. Monthly incidence data were examined in relation to monthly data for temperature, rainfall, rainfall anomalies, humidity and the Southern Oscillation Index for 1992–2001. Focusing on eight provinces, significant Pearson correlations were observed between dengue/DHF incidence and at least one climate variable ( r  = ±0.2 to ±0.43; P  < 0.05). Multiple regression analyses showed that 12.9–24.5 per cent of variance in incidence was explained by two or three climate variables in each province ( P  < 0.1–0.01). Rainfall appears to be the principal climatic agent affecting the geographic distribution and temporal pattern of incidence while temperature appears to play a critical role in outbreak intensity. Wide regional and temporal variations in the strength and nature of the observed associations led to the identification of three groups of provinces where increases in dengue/DHF incidence were variously associated with increased rainfall, decreased rainfall and/or high susceptibility to climate variability. Although climatic factors play an important role in explaining the timing and intensity of dengue/DHF outbreaks, a wide range of other factors specific to local environments also appear to be involved – information that may assist in the prediction and mitigation of regional dengue/DHF outbreaks.  相似文献   

7.
Data from apatite fission track analysis are presented for 20 outcrop samples collected in the southern Adelaide Fold Belt, South Australia. Interpretation of these data, with the aid of numerical models which allow inference of multiphase cooling histories, indicate three discrete cooling events that are likely to correlate with sedimentation events in surrounding depositional settings. An event beginning some time after 85 Ma (Late Cretaceous) was characterized by cooling throughout the study area from temperatures of roughly 50 to 70 °C. An event beginning at 300–270 Ma (Late Palaeozoic) was characterized by cooling from temperatures >120 °C in all areas except for the Mount Lofty Ranges and Murray Bridge region, where peak temperatures were only 95–115 °C prior to Palaeozoic cooling. Some samples from these subregions of relatively cool Late Palaeozoic temperatures also retain evidence for even earlier cooling from temperatures >120 °C, beginning prior to 350 Ma. We interpret the post 85-Ma event as the consequence of regional exhumation from a depth of 1.0–1.6 km. The Late Palaeozoic event (300–270 Ma) is interpreted as cooling associated with the termination of the Alice Springs Orogeny, while cooling prior to 350 Ma probably represents the final stages of Early Middle Palaeozoic unroofing of the southern Adelaide Fold Belt.
The results highlight the importance of regional, episodic postorogenic exhumation of Palaeozoic fold belts, where – in some cases – conventional methods have erroneously suggested relatively long-term stability.  相似文献   

8.
This paper presents results from a project designed to explore the meaning and function of partnership within the Catholic Church development chain. The geography literature has had little to say about such aid chains, especially those founded on faith-based groups. The relationships between three Catholic Church-based donors – referred to as A, B and C – with development personnel of the diocese of the Abuja Ecclesiastical Province (AEP) as well as other Catholic Church structures in Nigeria were analysed. The aim was to explore the forces behind the relationships and how 'patchy' these relationships were in AEP. Respondents were asked to give each of the donors a score in relation to four questions covering their relationship with the donors. Results suggest that the modus operandi of donor 'A' allows it to be perceived as the 'best' partner, while 'B' was scored less favourably because of a perception that it attempts to act independently of existing structures in Nigeria rather than work through them. There was significant variation between diocese in this regard, as well as between the diocese and other structures of the Church (Provinces, Inter-Provinces and National Secretariat). Thus 'partnership' in the Catholic Church aid chain is a highly complex, contested and 'visioned' term and the development of an analytical framework has to take account of these fundamentals.  相似文献   

9.
Abstract:  This paper examines how the cultural politics of resource management were played out on the North Kaipara beach between about 1900 and 1971 between Māori and the representative of the Crown, the Marine Department. Particular attention is devoted to how, after regulations were introduced to protect toheroa, the giant surf clam, Māori struggled to assert their rights through a range of transgressions. The paper argues that this illustrates how cultural politics works both from the top down (the Marine Department's implementation of policy) and the bottom up (Māori resistance). It concludes that through an examination of this particular 'culture war', the foreshore emerges as a contested domain where politics, culture and epistemology are inseparable.  相似文献   

10.
Abstract:  School should be a 'culturally safe' place, particularly for those students in Christchurch who challenge the city's reputation as a culturally homogeneous space and are thus frequently open to discrimination. A case study focusing on Somali refugee adolescents highlights that Christchurch's secondary schools – like those elsewhere in New Zealand – are not a culturally safe, certain space for all students but rather spatially reconstruct inequalities of gender, class and ethnicity. Yet, Somali students are not passive victims, for they have actively renegotiated these spaces within their schools with varying degrees of success.  相似文献   

11.
ABSTRACT. A Scots pine ( Pinus sylvestris L.) tree-ring width chronology from Jämtland, in the central Scandinavian Mountains, built from living and sub-fossil wood, covering the period 1632 BC to AD 2002, with a minor gap during AD 887–907, is presented. This is the first multi-millennial tree-ring chronology from the central parts of Fennoscandia. Pine growth in this tree line environment is mainly limited by summer temperatures, and hence the record can be viewed as a temperature proxy. Using the regional curve standardization (RCS) technique, pine-growth variability on short and long time scales was retained and subsequently summer (June–August) temperatures were reconstructed yielding information on temperature variability during the last 3600 years. Several periods with anomalously warm or cold summers were found: 450–550 BC (warm), AD 300–400 (cold), AD 900–1000 (the Medieval Warm Period, warm) and AD 1550–1900 (Little Ice Age, cold). The coldest period was encountered in the fourth century AD and the warmest period 450 to 550 BC. However, the magnitude of these anomalies is uncertain since the replication of trees in the Jämtland record is low during those periods. The twentieth century warming does not stand out as an anomalous feature in the last 3600 years. Two multi-millennial tree-ring chronologies from Swedish and Finnish Lapland, which have previously been used as summer temperature proxies, agree well with the Jämtland record, indicating that the latter is a good proxy of local, but also regional, summer temperature variability.  相似文献   

12.
Nick Gallent 《Area》2007,39(1):97-106
The word 'dwelling', to dwell, supposes engagement, in the sense that those who dwell are seen to engage with others and, in doing so, contribute to social capital and cohesion expressed in the forming of 'community'. Second home buying may be viewed as a course of action severing the process–product link between dwelling and community, as a brake on the community building process. In this paper, I contrast the view of dwelling as process – and its coupling with the 'traditional' place–community – with alternative notions of dwelling, and argue that the prevailing view is largely concerned with public and collective dwelling (and 'productive interaction'), and underplays the importance of private dwelling, and hence the self-identity and orientation – key aspects of dwelling – that flow from the use of private property, including the use of second homes.  相似文献   

13.
Summary. One hundred and eight deep-focus earthquakes occurring in the Indian region (6–37° N, 70–100° E) were originally selected for the study of P residuals (Paper I). Of these, 61 earthquakes were found suitable for analysing S residuals.
S times for this region are generally greater than J—B S times. Analysis of residuals reveals that anomalous regions are present both in the upper mantle as well as the lower mantle.  相似文献   

14.
This paper looks to the role of geographical metaphors in the 'battle of words' to describe Europe and its presumed identity. The facile adoption of banal cartographies such as those of a 'New' and 'Old' Europe highlights two concerns: first, that despite the imperial and isolationistic temptations of the current American administration, its geopolitical imagination remains firmly wedded to – indeed, cannot but define itself by – its relationship with the 'Old Continent'. Secondly, it reveals an astonishing distance between such cartographic abstractions and the variety of non-territorial metaphors – in particular, those of mediation and translation – that are increasingly being invoked to inscribe possible futures for the European project.  相似文献   

15.
Summary. A two-channel MESA or maximum entropy spectrum analysis (Morf et al. 1978) between Δ T °= ET – UT (Morrison 1973) and sunspot numbers spanning 1832–1975 yields the following results over a bandwidth 2–20yr: (1) The spectra of Δ T ° and sunspot numbers are both dominated by a narrow band signal at 11.0 yr; (2) On average the coherency over the continuum is 0.14 while at 11.0yr it peaks at 0.83; (3) The 11-yr sunspot cycle signal in length of day (lod) has an amplitude of 0.16 ms, and in time lags that in sunspot numbers by 3.4yr. Estimates obtained from segmenting the series yield extremal values which grossly bound the above estimates: The narrow band signal has period range (10.5–11.4yr) coherency (0.8–1.0), amplitude (0.06–0.31 ms), and time lag (3.0–3.Syr). In addition, a two channel analysis of sunspot numbers with a new Δ T n series from 1861–1978 (Morrison 1979) and an earlier segment of Δ T °, as well as a single-channel analysis of Δ T ° and Δ T n individually, further support the conclusion that the solar sunspot cycle in Earth rotation has been detected. These experimental results have implications in astronomy, solar physics, meteorology and climatology.  相似文献   

16.
The Barents Sea ice sheet - a sedimentological discussion   总被引:1,自引:0,他引:1  
Sediment sampling and shallow seismic profiling in the western and northern Barents Sea show that the bedrock in regions with less than 300 m water depth is unconformably overlain by only a thin veneer (<10 m) of sediments. Bedrock exposures are probably common in these areas. The sediments consist of a Holocene top unit, 0.1–1.5 m in thickness, grading into Late Weichselian glaciomarine sediments. Based on average sedimentation rates (14C-dating) of the Holocene sediments, the transition between the two units is estimated to 10,000–12,000 B.P. The glaciomarine sediments are commonly 1–3 m in thickness and underlain by stiff pebbly mud, interpreted as till and/or glaciomarine sediments overrun by a glacier. In regions where the water depth is over 300 m the sediment thickness increases, exceeding 500 m near the shelf edge at the mouth of Bjørnøyrenna. In Bjømøyrenna itself the uppermost 15–20 m seem to consist of soft glaciomarine sediments underlain by a well-defined reflector, probably the surface of the stiff pebbly mud. Local sediment accumulations in the form of moraine ridges and extensive glaciomarine deposits (20–60m in thickness) are found at 250–300m water depth, mainly in association with submarine valleys. Topographic highs, probably moraine ridges, are also present at the shelf edge. Based on the submarine morphology and sediment distribution, an ice sheet is believed to have extended to the shelf edge at least once during the Pleistocene. Spitsbergenbanken and the northern Barents Sea have also probably been covered by an ice sheet in the Late Weichselian. Lack of suitable organic material in the glacigenic deposits has prevented precise dating. Based on the regional geology of eastern Svalbard, a correlation of this younger stage with the Late Weichselian is indicated.  相似文献   

17.
Summary. Results from eight seismic refraction lines, 35–90 km long, in the Bristol Channel area are presented. The data, mostly land recordings of marine shots, have been interpreted mainly by ray-tracing and time-term modelling. Upper layer velocities through Palaeozoic rocks usually fall within the range 4.8–5.2 km s−1. Below the Carboniferous Limestone with a normal velocity of 5.1–5.2 kms−1, the Old Red Sandstone with a velocity of 4.7–4.8 kms−1 acts as a low velocity layer, as do parts of the underlying Lower Palaeozoic succession. In the central South Wales/Bristol Channel area and the Mendips, a 5.4–5.5 km s−1 refractor is correlated with a horizon at or near the top of the Lower Palaeozoic succession. Under the whole area, except for north Devon, a 6.0–6.2 km s−1 basal refractor has been located and is correlated with Precambrian crystalline basement rocks. In general, this refractor deepens southwards from a series of basement highs, which existed before the major movements of the Variscan orogeny in South Wales, resulting in a southerly thickening of the pre Upper Carboniferous supra-basement sequence. In north Devon, a 6.2 km s−1 refractor at shallow depth, interpreted as a horizon in the Devonian or Lower Palaeozoic succession, overlies a deep reflector that may represent the Precambrian crystalline basement.  相似文献   

18.
Net mass balance has been measured since 1958 at South Cascade Glacier using the 'direct method,' e.g. area averages of snow gain and firn and ice loss at stakes. Analysis of cartographic vertical photography has allowed measurement of mass balance using the 'geodetic method' in 1970, 1975, 1977, 1979–80, and 1985–97. Water equivalent change as measured by these nearly independent methods should give similar results. During 1970–97, the direct method shows a cumulative balance of about −15 m, and the geodetic method shows a cumulative balance of about −22 m. The deviation between the two methods is fairly consistent, suggesting no gross errors in either, but rather a cumulative systematic error. It is suspected that the cumulative error is in the direct method because the geodetic method is based on a non-changing reference, the bedrock control, whereas the direct method is measured with reference to only the previous year's summer surface. Possible sources of mass loss that are missing from the direct method are basal melt, internal melt, and ablation on crevasse walls. Possible systematic measurement errors include under-estimation of the density of lost material, sinking stakes, or poorly represented areas.  相似文献   

19.
Summary. The latitude of the Sq ( H ) focus along the 0° longitude meridian in the northern hemisphere has been determined for all the quiet days, as determined from the aa indices, for the sunspot minimum years 1963–64–65. It is shown that: (a) most of the large variability of the focus latitude is due to the effect of a superposed northward magnetic field that is present on AQDs and which tends to move the apparent focus latitude poleward in the northern hemisphere, and (b) a smaller equatorward motion is caused by the negative AQD events that occur in the 0830–1330 LT range. When these two classes of days are removed from the data set, the focus latitude is found to be completely contained within the range 36°-48° for the months March-October
with an average value of 41.5 ± 2.3, whilst in winter the range is larger with an average value of 36.7 ± 3.4. However, since the magnitude of the superposed northward field is longitude-dependent, it may be present even on days not classed as AQDs. It is shown that much of the variability in the focus latitude of the normal days along the 0° longitude meridian is caused by variations in the amplitude of the superposed northward field.  相似文献   

20.
Summary. An improved finite difference scheme is applied to simulate wave propagation in the vicinity of a slot normal to the surface of an elastic half space. It provides visualization of the scattered wave pattern at a sequence of time steps, and also the components of displacement as functions of time at a series of observation points.
After being hit by a normally incident plane P pulse, the slot oscillates with two main cycles and two shear-compressional pairs of diffracted waves, and also Rayleigh pulses, are scattered from it. The resulting wavefronts are parallel to the vertical surfaces of the slot and curve in semicircular arcs around the bottom of the slot.
Experimental tests of the theory were performed, using 0.5–6 MHz ultrasonic pulses on duralumin cylinders with surface-breaking slots ranging from 0.5–2 mm in width and from 2–6 mm in depth. The numerical results were confirmed by these experiments.  相似文献   

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